Supplemental Technical Specification for
Geotextile Soil Reinforcement
SCDOT Designation: SC-M-203-3 (01/18)
1.0 DESCRIPTION
1.1 The requirements of this specification consist of furnishing all necessary submittals and materials for providing geotextile soil reinforcement in accordance with the details shown on the plans and the requirements of this Supplement Technical Specification (STS, the project Specifications, Special Provisions or as directed by the Resident Construction Engineer (RCE). For geotextiles used for subgrade stabilization see STS Geosynthetic Materials for Separation and Stabilization (SC-M-203-1).
2.0 TESTING STANDARDS
2.1 Use the latest edition of the testing standards indicated in this specification. Substitution of standards will require the prior written approval of the Materials and Research Engineer (MRE) with concurrence of the Geotechnical Engineer-of-Record (GEOR). Provide copies of all substituted standards to the Resident Construction Engineer (RCE) if requested. The RCE will provide the copies to the MRE and GEOR for approval and concurrence.
3.0 MATERIAL
3.1 A geotextile is defined as permeable planar polymeric material used with foundation, soil, rock, earth, or any other geotechnical engineering related material, as an integral part of a civil engineering project, structure, or system. Geotextiles use fibers or yarns formed into a stable network. The structure of the geotextile reinforcements shall be dimensionally stable and be able to retain its geometry including selvages (edges), during shipping, handling, placement, and under construction stresses and have high resistance to damage during construction, to ultraviolet degradation, and to all forms of chemical and biological degradation encountered in the soil being reinforced. Geotextiles and the thread used in joining (seaming) geotextiles are manufactured from fibers consisting of long-chain polymers, composed of at least 95 percent by weight of polyolefins or polyesters. The geotextile shall be free from defects or tears. Supply only woven geotextiles unless otherwise indicated on the plans or in the Special Provisions. Geotextile design requirements and placement shall be as shown in the plans and shall meet the properties specified in Section 3.2.
3.2 Provide woven geotextiles meeting the following minimum allowable long-term reinforcement tension load, Tal or the tension load at 5 percent strain, T5 in the machine direction as indicated in the table below depending on the proposed application of the geotextile soil reinforcement. The proposed application of the geotextile soil reinforcement is indicated on the project plans, along with whether Tal or T5 is required. Tal is the Minimum Average Rolled Value (MARV) Tult that is reduced for construction installation damage, creep and durability. Similarly, T5 is the MARV at 5 percent strain. Obtain the following information from the grain- size testing of the proposed borrow materials and the subgrade if geotextile soil reinforcement will be placed directly on the subgrade:
D10 = Diameter of particle at 10% finer material, millimeter (mm) D60 = Diameter of particle at 60% finer material, mm D85 = Diameter of particle at 85% finer material, mm 1
% No. 200 = Percent material passing the No. 200 Sieve, %